We propose to record averaged brainstem potentials evoked by auditory stimuli (BER) from the vertex of normal infants and children, examining the maturational progression of latency, amplitude and waveform of the seven waves which may be elicited. These will be correlated with similar data obtained from the cortically-evoked response. The effect of rate of stimulus presentation is also being evaluated from birth to 5 years of age. These normative data will be contrasted with comparable data from "high-risk" infants, particularly those who have suffered documented episodes of hypoxemia during the perinatal period, and from older infants, who have suffered a period of asphyxia in early childhood. The findings will be correlated with the clinical outcome, short- and long-term. We will attempt to determine the usefulness of the BER in monitoring the effect of acute perinatal hypoxia on current brain function and in predicting late neurological sequellae. BIBLIOGRAPHIC REFERENCES: Salamy, A. and McKean, C.M., Postnatal development of human brainstem potentials during the first year of life, EEG clin. Neurophysiol. 40 (1976) 418-426. Salamy, A. and McKean, C.M., Habituation and dishabituation of cortical and brainstem evoked potentials, Int. J. Neurosci. (1977). In press.